1. Field of the Invention
The invention is directed to additives which are particularly useful in hydrocarbon fuels. The additives of this invention are particularly suited for use in hydrocarbon fuels subject to fuel injection or other mechanisms to achieve atomization. Throughout the specification, numerous references will be made to the use of the additives in diesel fuels. However, it should be realized that the inventive additive can also be used in other hydrocarbon base fuels.
2. Description of the Art
In the production of hydrocarbon fuels, and in particular, diesel fuels, a variety of additives are often employed. For example, demulsifiers are supplied in additive packages such as Lubrizol.RTM. 560, 544, and 8022A to reduce the emulsification of middle distillate fuels and/or gasoline in storage tanks. In addition, wax modifiers are present in additive packages such as Lubrizol.RTM. 8069, to facilitate the dispersion of wax in hydrocarbon fuels. Fuel additives such as low temperature flow improvers, cetane improvers, dyes, antioxidants, rust inhibitors, bacteriostatic agents, gum inhibitors, metal deactivators, detergent/dispersant deposit inhibitors or cleaners, and anti-icing agents are often employed to address particular limitations of hydrocarbon fuels.
Atomization is another focus of those interested in hydrocarbon fuels. Obviously, fuel flowability and atomization are important elements to facilitate a quick, complete, and intense burn in the engine. It is believed, although not wishing to be bound by theory, that a higher degree of atomization increases the surface area of the fuel making combustion more efficient. Generally, at room temperatures and higher operating temperatures, the fuel's ability to flow and atomize is relatively good; however, lower temperatures reduce fuel flowability and atomization. In the instant invention, an additive is provided which particularly improves low temperature atomization.
It should be noted that the atomization of fuel is attacked on two primary fronts. A first focus is the mechanical means of achieving atomization, i.e. fuel injection designs. A second focus in on the chemical characteristics of the fuel, i.e. molecular attractions/repulsions which can be modified with fuel additives. Accordingly, atomization is a well studied phenomena, a fundamental description of which can be found in Fuel Spray Technology (SP-1026), published by The Society of Automotive Engineers, Inc. (2/94).